Hasan, R. T. S., T. Machmud, K. A. Y. Pauweni, and S. Ismail. “Development of the ‘GAULL’ Mathematics Learning E-Module Using Crossword Games on Flat-Side Space Buildings”. Numerical: Jurnal Matematika Dan Pendidikan Matematika, vol. 8, no. 1, July 2024, pp. 125-38, doi:10.25217/numerical.v8i1.4951.